Test device for a surgical tool

ABSTRACT

In various embodiments, a surgical test device for a surgical tool, such as a severing and/or sealing tool (e.g., a surgical stapler), is provided. In at least one embodiment, the surgical tool can be configured to supply at least one actuation motion to an end effector. The actuation motion(s) may cause a cutting member to move within and/or sealing members (e.g., staples) to eject from the end effector. Further, in at least one embodiment, the surgical test device can be releasably engaged to a portion of the surgical tool, such as the end effector. Additionally, the surgical test device can be configured to permit the surgical tool to supply the actuation motion(s) while preventing the tool from performing its intended surgical function. Accordingly, the surgical tool may be test fired without wasting a sealing member cartridge, while preventing inappropriate use of the tool when the test device is attached thereto.

BACKGROUND

The embodiments relate, in general, to surgical sealing and severing tools, such as a surgical stapler or endocutter, and, more particularly, to a test device for such a surgical tool.

An endocutter is a surgical stapler instrument that is capable of applying lines of staples to tissue while cutting the tissue between those staple lines. Surgical staplers have been used in the field to simultaneously make a longitudinal incision in tissue and apply lines of staples on opposing sides of the incision. Such instruments commonly include a pair of cooperating jaw members that, if the instrument is intended for endoscopic or laparoscopic applications, are capable of passing through a cannula passageway. One of the jaw members receives a staple cartridge having at least two laterally spaced rows of staples. The other jaw member defines an anvil having staple-forming pockets aligned with the rows of staples in the cartridge. The instrument includes a plurality of reciprocating wedges which, when driven distally, pass through openings in the staple cartridge and engage drivers supporting the staples to effect the firing of the staples toward the anvil.

An example of a surgical stapler suitable for endoscopic applications is described in U.S. Pat. Application Pub. No. 2004/0232196 A1, the disclosure of which is incorporated herein by reference in its entirety, which advantageously provides distinct closing and firing actions. Thereby, a clinician is able to close the jaw members upon tissue to position the tissue prior to firing. Once the clinician has determined that the jaw members are properly gripping tissue, the clinician can then fire the surgical stapler, thereby severing and stapling the tissue. The simultaneous severing and stapling avoids complications that may arise when performing such actions sequentially with different surgical tools that respectively only sever or staple.

It is often advantageous to build an end effector for the surgical stapler that is reusable. For instance, one patient may need a series of severing and stapling operations during a surgical procedure. Replacing an entire end effector for each operation during the procedure tends to be economically inefficient. This is especially true if the end effector is built to be strong and reliable over repeated operations. To that end, staple cartridges are fitted into the end effector prior to each operation of the surgical stapler. Thus, a much smaller amount of the surgical stapler is discarded after each use.

Further, while the staple cartridge provides numerous advantages, it is desirable to prevent inadvertent firing of the surgical stapler when an unfired staple cartridge is not present. Otherwise, the severing of tissue may occur without the staples present to minimize bleeding and/or leaking. Accordingly, some surgical staplers are equipped with a lockout mechanism to prevent firing unless an unfired staple cartridge is present. Exemplary surgical staplers including a lockout mechanism may include those described in the following documents, the disclosures of which are hereby incorporated by reference in their respective entireties: U.S. patent application Ser. No. 10/441,424, entitled “SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING,” to Shelton, IV et al. (which issued as U.S. Pat. No. 7,044,352); U.S. patent application Ser. No. 10/441,565, entitled “SURGICAL STAPLING INSTRUMENT HAVING A SPENT CARTRIDGE LOCKOUT,” to Shelton, IV et al. (which issued as U.S. Pat. No. 6,988,649); U.S. patent application Ser. No. 10/687,503, entitled “SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING,” to Doll et al. (which issued as U.S. Pat. No. 7,380,695); U.S. patent application Ser. No. 11/066,371, entitled “SURGICAL STAPLING INSTRUMENT HAVING AN ELECTROACTIVE POLYMER ACTUATED SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING,” to Shelton, IV et al. (which issued as U.S. Pat. No. 7,140,528); U.S. patent application Ser. No. 11/266,961, entitled “LOCKOUT MECHANISMS AND SURGICAL INSTRUMENTS INCLUDING SAME,” to Ortiz et al. (which published as U.S. Pat. App. Pub. No. 2007/0102475); and U.S. patent application Ser. No. 11/651,788, entitled “INTERLOCK AND SURGICAL INSTRUMENT INCLUDING SAME,” to Shelton, IV et al. (which published as U.S. Pat. App. Pub. No. 2008/0167670).

The foregoing discussion is intended only to illustrate the present field and should not be taken as a disavowal of claim scope.

SUMMARY

In various embodiments, a surgical instrument is provided. In at least one embodiment, the surgical instrument can comprise a surgical tool and a surgical test device releasably engaged to at least a portion of the surgical tool. In these embodiments, the surgical tool can be configured to supply at least one actuation motion to an end effector. Further, in these embodiments, the surgical tool can be configured to perform an intended surgical function. Moreover, in these embodiments, the surgical test device can be configured to permit the surgical tool to supply the at least one actuation motion while preventing the surgical tool from performing the intended surgical function.

In various embodiments, a surgical test device is provided. In at least one embodiment, the surgical test device can comprise a body that is sized and configured to engage an end effector of a surgical tool and a release member that is coupled to the body. In these embodiments, the body can lack sealing member openings and the release member can be configured to engage a lockout mechanism on the surgical tool.

In at least one embodiment, a surgical test device is provided that can comprise a body and a release member that is coupled to the body. In these embodiments, the body can comprise at least two side walls and a bottom wall. Further, in these embodiments, the side walls can extend from the bottom wall. Additionally, in these embodiments, the side walls and the bottom wall can define a cavity, and the cavity can be sized and configured to receive at least a portion of an end effector of a surgical tool. Moreover, in these embodiments, the release member can be configured to engage a lockout mechanism on the surgical tool.

BRIEF DESCRIPTION OF THE FIGURES

The novel features of the embodiments described herein are set forth with particularity in the appended claims. The embodiments, however, both as to organization and methods of operation may be better understood by reference to the following description, taken in conjunction with the accompanying drawings as follows.

FIG. 1 is a left perspective view of a non-limiting embodiment of a surgical stapler including a handle, a shaft, and an end effector including a staple cartridge.

FIG. 2 is a side view of the surgical stapler of FIG. 1.

FIG. 3 depicts a bottom perspective view of the proximal end of the staple cartridge of FIG. 1 showing a sled in an unfired position.

FIG. 4 depicts an isometric view of the end effector of FIG. 1 with an anvil in an up or open position exposing the staple cartridge and a cutting member.

FIG. 5 is a right perspective view of a non-limiting embodiment of a surgical instrument including a surgical test device attached to the end effector of the surgical stapler of FIG. 1.

FIG. 6 is a side view of the surgical instrument of FIG. 5.

FIG. 7 is a front perspective view of the surgical test device attached to the end effector of FIG. 5; the end effector is shown in an open position and the test device is shown in transparency for clarity.

FIG. 8 is a front perspective view of the surgical test device attached to the end effector of FIG. 5; the end effector is shown in a closed position and the test device is shown in transparency for clarity.

FIG. 9 is top perspective view of the surgical test device of FIG. 5, shown unattached to an end effector.

FIG. 10 is a side cross-sectional view of the surgical test device of FIG. 5 attached to an end effector of a surgical stapler; two jaw members are illustrated in a closed position and a cutting member is shown in transparency for the purposes of clarity; various additional components of the end effector and a surgical stapler are omitted also for the purposes of clarity.

FIG. 11 is a partial perspective cross-sectional view of the surgical test device attached to the end effector of the surgical stapler of FIG. 5.

FIG. 12 is a partial side cross-sectional view of the end effector of FIG. 10 illustrating the cutting member resting in a lockout trough in a locked position.

FIGS. 13A-13C illustrate the surgical test device attached to the end effector of FIG. 10 as the cutting member is moved into a release member of the test device and over the lockout trough.

FIG. 14 is a perspective view of a non-limiting embodiment of a surgical test device.

FIG. 15 is a side cross-sectional view of the surgical test device of FIG. 14.

FIG. 16 is a bottom view of the surgical test device of FIG. 14.

FIG. 17 is a top perspective view of a non-limiting embodiment of a surgical test device.

FIG. 18 is a bottom perspective view of a proximal portion of the surgical test device of FIG. 17.

FIG. 19 depicts a bottom perspective view of the proximal end of a non-limiting embodiment of a surgical test device showing a sled in an unfired position.

FIG. 20 depicts an isometric view of the surgical test device of FIG. 19 inserted in the end effector of FIG. 1, in place of the staple cartridge.

FIG. 21 is a side perspective view of a non-limiting embodiment of a surgical test device.

DETAILED DESCRIPTION

Certain embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the devices and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those of ordinary skill in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting embodiments and that the scope of these embodiments is defined solely by the claims. The features illustrated or described in connection with one embodiment may be combined with the features of other embodiments. Further, where an ordering of steps in a process is indicated, such ordering may be rearranged or the steps may be carried out contemporaneously as desired unless illogical or the listed order is explicitly required. Such modifications and variations are intended to be included within the scope of the appended claims.

In the following description, like reference characters designate like or corresponding parts throughout the several views. Also in the following description, it is to be understood that terms such as “forward,” “rearward,” “front,” “back,” “right,” “left,” “over,” “under,” “upwardly,” “downwardly,” “proximally,” “distally,” and the like are words of convenience and are not to be construed as limiting terms. The description below is for the purpose of describing various embodiments and is not intended to limit the appended claims.

The various embodiments generally relate to various surgical test devices configured to override a sealing member lockout on a surgical severing and/or sealing tool, such as a surgical stapler or endocutter. Such surgical staplers may be configured to function through a natural orifice, such as the anus, mouth and/or vagina, or through an incision cut through a body wall. Further, such surgical staplers may be designed as endoscopic tools, including laparoscopic tools. In any event, a surgical test device, according to various embodiments described herein, may allow a surgeon, nurse, or other user to fire and test the surgical stapler to ensure that the device is working properly before using the stapler on a patient. As will be seen, a surgical test device may be a low-cost disposable unit that facilitates the test firing of a surgical tool for one or more actuation cycles without damaging the surgical tool or using more expensive sealing member cartridges, such as staple cartridges or similar replaceable units. A surgical test device may be removed after a brief test and replaced by an actual sealing member cartridge, such as a staple cartridge and/or fastener reload unit, prior to use on a patient.

Focusing now on one exemplary surgical stapler, the surgical stapler 10 depicted in FIGS. 1 and 2 may comprise a handle 6, a shaft 8, and an end effector 12 connected to the shaft 8. In various embodiments, the end effector 12 can be articulated about an articulation pivot 14 located in a distal portion of shaft 8. One or more rotation and/or articulation controls 16′, 16″ may be provided adjacent to the handle 6 to effect rotation of the end effector 12 about the articulation pivot 14. In the illustrated embodiment, the end effector 12 is configured to act as an endocutter for clamping, severing and stapling tissue, although, in other embodiments, different types of end effectors may be used, such as end effectors for other types of surgical devices, such as graspers, cutters, staplers, clip appliers, access devices, drug/gene therapy devices, ultrasound, RF or laser devices, etc. More details regarding RF devices may be found in U.S. Pat. No. 5,403,312 and U.S. patent application Ser. No. 12/031,573, entitled “SURGICAL CUTTING AND FASTENING INSTRUMENT HAVING RF ELECTRODES,” filed Feb. 14, 2008, the disclosures of which are hereby incorporated by reference in their entireties.

The handle 6 of the stapler 10 may include a closure trigger 18 and a firing trigger 20 for actuating the end effector 12. It will be appreciated that staplers having end effectors directed to different surgical tasks may have different numbers or types of triggers or other suitable controls for operating the end effector 12. The end effector 12 is shown separated from the handle 6 by the elongate shaft 8. In one embodiment, a clinician or operator of the stapler 10 may articulate the end effector 12 relative to the shaft 8 by utilizing the articulation controls 16′ and/or 16″, as described in more detail in published U.S. patent application Pub. No. 2007/0158385 A1, entitled “SURGICAL INSTRUMENT HAVING AN ARTICULATING END EFFECTOR,” by Geoffrey C. Hueil et al., which is incorporated herein by reference in its entirety. Additional details regarding articulating end effectors and their control may be found in one or more of the following U.S. patent applications, the disclosures of each being hereby incorporated by reference in their respective entireties: (1) “SURGICAL INSTRUMENT INCORPORATING AN ARTICULATION MECHANISM HAVING ROTATION ABOUT THE LONGITUDINAL AXIS”, Ser. No. 10/615,973, now U.S. Pat. No. 7,111,769, to Frederick E. Shelton, Brian J. Hemmelgarn, Jeff Swayze, Kenneth S. Wales, filed 9 Jul. 2003; (2) “SURGICAL STAPLING INSTRUMENT INCORPORATING AN ARTICULATION JOINT FOR A FIRING BAR TRACK”, Ser. No. 10/615,962, now U.S. Pat. No. 6,786,382 to Brian J. Hemmelgarn, filed 9 Jul. 2003; (3) “A SURGICAL INSTRUMENT WITH A LATERAL-MOVING ARTICULATION CONTROL”, Ser. No. 10/615,972, now U.S. Pat. No. 6,981,628, to Jeff Swayze, filed 9 Jul. 2003; (4) “SURGICAL STAPLING INSTRUMENT INCORPORATING A TAPERED FIRING BAR FOR INCREASED FLEXIBILITY AROUND THE ARTICULATION JOINT”, Ser. No. 10/615,974, now U.S. Pat. No. 7,055,731, to Frederick E. Shelton, Mike Setser, Bruce Weisenburgh, filed 9 Jul. 2003; and (5) “SURGICAL STAPLING INSTRUMENT HAVING ARTICULATION JOINT SUPPORT PLATES FOR SUPPORTING A FIRING BAR”, Ser. No. 10/615,971, now U.S. Pat. No. 6,964,363, to Jeff Swayze, Joseph Charles Hueil, filed 9 Jul. 2003.

The end effector 12 includes, in this example, among other things, a sealing member cartridge channel, such as staple cartridge channel 22, and a pivotally translatable clamping member, such as an anvil 24, which are maintained at a spacing that assures, when the anvil 24 is in its clamped or closed position, effective stapling and severing of tissue clamped in the end effector 12. As discussed in more detail below, the staple cartridge channel 22 may releasably retain a staple cartridge 37 containing staples. The handle 6 includes a downwardly extending pistol grip 25, towards which a closure trigger 18 is pivotally drawn by the clinician to cause clamping or closing of the anvil 24 toward the staple cartridge channel 22 of the end effector 12 to thereby clamp tissue positioned between the anvil 24 and channel 22. The firing trigger 20 is farther outboard of the closure trigger 18. Once the closure trigger 18 is locked in the closure position, the firing trigger 20 may rotate slightly toward the pistol grip 25 so that it can be reached by the operator using one hand. Then the operator may pivotally draw the firing trigger 20 toward the pistol grip 25 to cause the stapling and severing of clamped tissue in the end effector 12. In other embodiments, different types of clamping members besides the anvil 24 could be used. The handle 6 may also include an upper portion 28 that may sit on top of the user's hand when the user grips the pistol grip portion 25 with his/her hand.

It will be appreciated that the terms “proximal” and “distal” are used herein with reference to a clinician gripping the handle 6 of an stapler 10. Thus, the end effector 12 is distal with respect to the more proximal handle 6. It will be further appreciated that, for convenience and clarity, spatial terms such as “vertical” and “horizontal” are used herein with respect to the drawings. However, surgical staplers are used in many orientations and positions, and these terms are not intended to be limiting and absolute.

In operational use, referring still to FIGS. 1 and 2, the closure trigger 18 may be actuated first. Once the clinician is satisfied with the positioning of the end effector 12, the clinician may draw back the closure trigger 18 to its fully closed, locked position proximate to the pistol grip 25. The firing trigger 20 may then be actuated. The firing trigger 20 returns to the open position (shown in FIGS. 1 and 2) when the clinician removes pressure. A release button on the handle 6, when depressed may release the locked closure trigger 18. The release button may be implemented in various forms such as, for example, as disclosed in published U.S. Patent application Pub. No. 2007/0175955, entitled “SURGICAL CUTTING AND FASTENING INSTRUMENT WITH CLOSURE TRIGGER LOCKING MECHANISM,” which is incorporated herein by reference in its entirety.

Referring to FIG. 4, the end effector 12 may include a cutting member 26, comprising a knife, for example, for cutting tissue clamped in the end effector 12 when the firing trigger 20 is retracted by a user. The end effector 12 may also comprise means for fastening and/or sealing the tissue severed by the cutting member, such as staples, two-part fasteners, RF electrodes, adhesives, etc. More details regarding possible configurations of the end effector 12 may be found in the following patents and published patent applications, which are incorporated herein by reference in their entirety: U.S. Pat. No. 5,709,680; U.S. Pat. No. 5,688,270; U.S. Pat. No. 7,000,818; Pub. No. 2005/0173490 A1; Pub. No. 2006/0025809 A1; Pub. No. 2007/0102453 A1; No. 2007/0102452 A1; Pub. No. 2009/0206134 A1; and Pub. No. 2009/0206124 A1.

Referring back to FIGS. 1 and 2, the stapler 10 may also comprise a closure system for closing (or clamping) the end effector upon closure (or retraction) of the closure trigger 18. More details regarding embodiments of an exemplary closure system for closing (or clamping) the anvil 24 of the end effector 12 by retracting the closure trigger 18 are provided in the following U.S. patent references, which are incorporated herein by reference in their respective entireties: Pub. No. 2004/0232196 A1; Pub. No. 2007/0175956 A1; Pub. No. 2007/0158385 A1; Pub. No. 2007/0175962 A1; U.S. Pat. No. 7,464,849; and the references cited in the paragraph above.

A longitudinally movable drive shaft located within the shaft 8 of the stapler 10 may drive/actuate the cutting member and the fastening means in the end effector 12. An electric motor, located in the pistol grip portion 25 of the handle 6 of the stapler 10, may be used to drive, indirectly, the drive shaft, as described further herein. In various embodiments, the motor may be a DC brushed driving motor having a maximum rotation of, approximately, 25,000 RPM. In other embodiments, the motor may include a brushless motor, a cordless motor, a synchronous motor, a stepper motor, or any other suitable electric motor. A battery (or “power source” or “power pack”), such as a Li ion battery, may be provided in the pistol grip portion 25 of the handle 6 adjacent to the motor. The battery supplies electric power to the motor via a motor control circuit. According to various embodiments, a number of battery cells connected in series may be used as the power source to power the motor. In addition, the power source may be replaceable and/or rechargeable. Additional details regarding surgical stapler 10 may be found in U.S. patent application Ser. No. 12/647,100, now U.S. Pat. No. 8,220,688, entitled “MOTOR-DRIVEN SURGICAL CUTTING INSTRUMENT WITH ELECTRIC ACTUATOR DIRECTIONAL CONTROL ASSEMBLY,” filed on Dec. 24, 2009, the disclosure of which is hereby incorporated by reference in its entirety.

As noted above, the surgical stapler 10 may include a staple cartridge lockout. In particular, various components of such a lockout within and/or coupled to the end effector 12 may prevent the cutting member 26 and/or a staple driver sled 38, within the end effector 12, from actuating unless an unspent staple cartridge 37 is present in staple cartridge channel 22. Exemplary lockouts and staple cartridges may be found in U.S. patent application Ser. No. 10/687,503, entitled “SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING,” to Doll et al. (issued as U.S. Pat. No. 7,380,695), mentioned above among others.

An exemplary staple cartridge 37 is illustrated in FIGS. 3-4. The staple cartridge 37 may be sized and configured to be received at least partially within staple cartridge channel 22. The staple cartridge 37 may include a sled 38 that is configured to be driven by a cutting member 26 located within the end effector 12. Accordingly, as cutting member 26 is fired and moves sled 38 in distal direction “DD,” staples (not shown) may be ejected from staple cavities and through sealing member or staple openings 39. As used herein, a sealing member may include, but is not limited to, staples, two-part fasteners, adhesives, and the like. Accordingly, in various embodiments, a sealing member opening, such as staple openings 39, may be configured to eject a sealing member therethrough.

While a staple cartridge lockout may be useful to prevent inadvertent firings of the stapler, a user, such as a surgeon or an operating room staff person, may desire to test each instrument prior to using it and/or presenting it to the surgeon. This may be especially true for electrically powered surgical instruments that require battery assembly. For example, a nurse typically runs a surgical drill for 1-3 seconds after connecting the battery and before handing the drill to a surgeon, ensuring the drill and battery are functioning properly. However, a surgical stapler, such as stapler 10, may come equipped with the aforementioned safety lockout to prevent the device from functioning until it is properly and fully setup and placed in the actual surgical environment. Specifically, many instruments can only be test-fired by inserting and firing an actual fastener cartridge/reload, which could be costly and/or dangerous to do in the operating room instrument prep area (colloquially known as the “back table”). Such lockouts may prevent an operating room nurse, for example, from doing the testing necessary to gain confidence that the device is functional.

Focusing now on at least one non-limiting embodiment, as can be seen in FIGS. 5-6, a surgical instrument 1 is shown that may comprise a surgical tool, such as stapler 10, that may be configured to supply an actuation motion or motions to an end effector 12, and a surgical test device, such as test device 100. As discussed above, the actuation motion(s) may cause a cutting member to move through the end effector and/or eject sealing members, e.g., staples, from the end effector. Further, the surgical tool may be configured to perform an intended surgical function, such as eject a sealing member or members from the end effector 12, be passed, at least partially, through a trocar or cannula (e.g., the end effector 12 and/or shaft 8 may be sized and configured to fit through the inner lumen of a trocar), and/or receive tissue within the end effector 12. Also, the surgical test device may be configured to permit the surgical tool to supply the actuation motion or motions to the end effector, while preventing the surgical tool from performing at least one of its intended surgical functions.

In more detail, in one embodiment, the surgical test device 100 may be releasably attached to the end effector 12 of a surgical stapling and/or severing tool, such as stapler 10, is shown. The end effector 12 may comprise a cutting member. Further, the surgical stapler 10 may also include a lockout mechanism, discussed below, configured to prevent the cutting member 26 from moving within the end effector 12 when the lockout engages at least a portion of the cutting member 26 (see FIG. 4). As used herein and as described in more detail below, the lockout mechanism may include various portions of the surgical tool, such as, but not limited to, portions of the cutting member and/or the end effector. Further, the test device 100 may comprise a body 101 releasably engaged to the end effector 12. Unlike a staple cartridge, the body lack staple cavities or slots for ejecting staples therethrough, and, accordingly, the test device need not include staples. Further, also discussed in more detail below, a release member may be coupled to the body and be configured to engage at least a portion of the lockout mechanism to prevent the lockout mechanism from engaging the cutting member 26, thereby allowing one to test fire the surgical stapler 10, without fear of ejecting a sealing member or members, such as staples, therefrom.

The surgical test device 100 may further prevent or reduce the probability that the device will be improperly used without an unspent staple cartridge. For example, referring to FIGS. 5 and 6, the test device 100, owing to its relative size and when attached to a surgical stapling and/or severing tool, such as stapler 100, may prevent the end effector 12 from being inserted into and/or through a trocar. In more detail, the surgical test device may further comprise a bottom wall 105 and at least one side wall, such as side walls 102 and 103, extending from the bottom wall 101. Further, an end wall, such as end wall 104, for example, may also extend from the body 101 and connect with side walls 102, 103. The bottom wall may be adjacent to the staple cartridge channel 22 and the side walls and/or end wall 104 may extend past staple cartridge channel 22 toward and/or past anvil 24. Referring briefly to FIG. 9, the side walls 102, 103, end wall 104, and/or bottom wall 105 may define a cavity 106 that is sized and configured to receive at least a portion of the end effector 12. In any event, referring back to FIGS. 5 and 6, the side walls 102, 103 and/or end wall 104 may be size and configured to be larger than a trocar through which end effector 12 (when closed) and/or shaft 8 may normally, absent test device 100, fit. In other words, the side walls 102, 103 and/or end wall 104 may serve as a guard against inserting the surgical instrument 1 through a trocar until a user removes test device 100 and inserts an unspent staple cartridge 37 (see FIGS. 3-4).

Additionally, the surgical test device 100 may help prevent or reduce the probability that a user or another person may be unintentionally injured by the stapler 10, or that a patient's tissue is cut without sealing members, e.g., staples, in the stapler 10. Referring to FIGS. 7 and 8, the surgical test device 100 is shown in transparency for clarity. The test device 100 is attached to the end effector 12, which is shown in an open position (FIG. 7) and a closed position (FIG. 8). As can be seen, the end effector's two jaw members, e.g., staple cartridge channel 22 and anvil 24, are movable between the aforementioned open and closed positions and at least one of side walls 102, 103 and/or end wall 104 may be sized and configured to cover the staple cartridge channel 22 and anvil 24 when the channel 22 and 24 are in the open position. In other words, one or more of side walls 102, 103 and/or end wall 104 may extend away from the bottom wall 105, past the open position (FIG. 7) of the anvil 24. Further, one or more of side walls 102, 103 may have a sloped profile, as shown, that correlates with the open position of the anvil 24. The angle of the walls' profile may be substantially equal to the angle of the open position of the anvil 24. These angles may be measured with respect to the bottom wall 105 and/or staple cartridge channel 22, which may be substantially parallel in orientation. Such a sloped profile of side walls 102, 103 may reduce the amount of material needed to manufacture surgical test device 100. In any event, the side walls 102, 103, and/or end wall 104 may serve as a guard to ensure that an unintended object, such as a patient's tissue and/or a non-patient's finger, for example, are not inserted into the surgical stapler 10 while the test device 100 is positioned on end effector 12. Accordingly, one may be protected from the cutting member 26 (see FIG. 4) and/or other sharp features of the end effector 12.

The surgical test device 100 may be further configured to disable a lockout feature of the surgical stapler 10. For example, the test device 100 may include a release member, such as release member 107, that may be coupled to the body 101 and be configured to engage the lockout to prevent the same from engaging the cutting member, thereby allowing one to test fire the stapler 10 without wasting a staple cartridge 37 (see FIGS. 3-4). Referring to FIG. 9, a top perspective view of the surgical test device 100 is shown unattached to an end effector. FIG. 10 also shows a side cross-sectional view of the surgical test device 100 attached to an end effector 12 of surgical stapler 10 (see FIGS. 1-2). In FIG. 10, two jaw members, e.g., staple cartridge channel 22 and anvil 24, and a cutting member 26 are illustrated; however, various additional components are omitted for the purposes of clarity. Additional exemplary details regarding such components may again be found in U.S. patent application Ser. No. 10/687,503, entitled “SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING,” to Doll et al. (issued as U.S. Pat. No. 7,380,695), noted above. Further, the cutting member 26 is shown in transparency in FIGS. 10 and 12-13C for the purposes of clarity. Referring to FIGS. 9 and 10, the release member 107 may protrude from the bottom wall 105 of body 101. The release member 107 may be separately formed and then attached to the body 101, or the release member 107 may be unitary and integrally formed from the same piece of material as the body 101. Regardless, release member 107 may be positioned and configured to engage at least one component of a lockout mechanism of a surgical stapling and/or severing tool, such as stapler 10 (see FIGS. 1-2).

In more detail, portions of such a lockout mechanism may be best seen in FIGS. 11-12. FIG. 11 shows a partial perspective cross-sectional view of the surgical test device 100 attached to the end effector 10 of the surgical stapler 10. The cutting member 26 may be coupled to a firing bar 29 that is configured to apply an actuation or firing motion, to push, or to otherwise move the cutting member in a distal direction DD when the firing trigger 20 (see FIGS. 5-6) is actuated. Further, the firing bar may retract the cutting member 26 to a starting position shown in FIGS. 10 and 11, for example, upon completion of the firing stroke. The firing bar 29 may be biased toward the bottom of the staple cartridge channel 22 by a spring, such as leaf spring 31 that slidingly contacts a portion of firing bar 29. Further, the cutting member 26 may include wings or pins 27 that extend laterally therefrom. Thus, when the firing bar 29 drives the cutting member 26 in the distal direction DD, the cutting member 26, at least initially, and the pins 27 are driven towards the bottom of staple channel 22.

The staple channel 22 may further include a lockout trough 23 located near the starting position of the cutting member 26 that is sized and configured to receive the pins 27. Accordingly, when the cutting member 26 is moved distally from the starting position shown in FIGS. 10 and 11, the pins 27 may become lodged or otherwise stuck in trough 23, thereby preventing further distal movement of the cutting member 26, see FIG. 12. FIG. 12 illustrates the cutting member 26 resting in the lockout trough 23 in a locked position.

In normal use, referring to FIGS. 3 and 11, when a staple cartridge 37 is inserted in staple cartridge channel 22, a notch 32 at the distal portion of cutting member 26 may engage sled 38 and thereby prevent the pins 27 from moving into lockout trough 23. Further exemplary details regarding overcoming the lockout mechanism with a staple cartridge may be found in the above mentioned U.S. patent application Ser. No. 10/687,503, entitled “SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING,” to Doll et al. (issued as U.S. Pat. No. 7,380,695).

In at least one embodiment, the lockout may be overcome by the surgical test device 100. In other words, the surgical test device 100 may prevent the pins 27 from becoming lodged in lockout trough 23. Referring now to FIGS. 13A-13C, the surgical test device 100 is shown attached to the end effector 12 as the cutting member is moved into a release member of the test device and over the lockout trough. In more detail, FIG. 13A shows the cutting member 26 in a starting position, as mentioned above. FIG. 13B shows the cutting member 26 as it is being advanced in a distal direction DD. The cutting member 26 and pins 27 are being biased towards lockout trough 23 by spring 29 (see FIG. 11). However, as the pins 27 commence to enter the trough 23, a bottom portion 30 of cutting member 26 contacts a ramp or inclined surface 108 of release member 107. As the cutting member 26 is further fired in the distal direction DD, the cutting member 26 may slide up the inclined surface 108 to prevent the pins 27 from engaging the lockout trough 23. FIG. 13C shows the cutting member 26 as it is further advanced distally such that the bottom portion 30 slides along a plateau or elevated surface 109 formed in the body 101, for example, thereby allowing the cutting member 26 to smoothly move through the end effector 12.

While the cutting member 26 is moving distally through the end effector 12, a user may wish to observe or otherwise confirm the cutting member's travel therethrough, to ensure that the surgical stapler 10 (see FIG. 5) is functioning appropriately. Accordingly, in various embodiments, the surgical test device 100 may include features to inform a user that the stapler 10 is properly firing. In at least one embodiment, the user may visually see the cutting member 26 move. For example, referring again to FIG. 9, the test device 100 may include openings or slots 111 defined by end wall 104 and/or bottom wall 105. Further, referring to FIGS. 11 and 12, for example, the bottom portion 30 of the cutting member may be externally accessible and/or visible through a slot in the bottom of staple channel 22. Thus, when viewed from the underside, the advancement of cutting member 26, while surgical test device 100 is attached to end effector 12, may be at least partially viewed through slots 111 (see FIG. 9). Further, the body 101 may be transparent, thereby allowing one to also see the cutting member 26 move through the end effector 12 through one or more of walls 102, 103, 104, and 105.

The surgical test device 100 may be releasably engaged to an end effector 12 as follows. Flex or snap tabs 110 may be attached to, formed in, and/or defined by side walls 102, 103. Each tab 110 may be configured to releasably engage a portion of the end effector 12, such as staple cartridge channel 22 (see FIG. 10) and cooperate with bottom wall 105 to hold the end effector 12 thereto. Accordingly, referring to FIGS. 9 and 10, the end effector 12 may be pressed into cavity 106 until tabs 110 snap onto the staple cartridge channel 22, for example. The tabs 110 may also be configured to resist the forces created when the cutting member 26 contacts the release member 107, and thereby hold the test device 100 in place during firing of the cutting member 26.

Removing the surgical test device 100 from the end effector may be effectuated by pulling, twisting, and/or otherwise dislocating the tabs 110 from the end effector 12. In at least one embodiment, the test device's body 101 may be flexible and/or made of a resilient plastic material or materials. Further, the slot 111 defined by end wall 104 may be open at the top of the test device 100, see FIG. 9, thereby better allowing the body 101 to be pealed off the end effector 12, owing to separation between portions of end wall 104. Also, the test device 100 may further comprise at least one finger tab or grip 112 extending from the at least one side wall such that a user may grip the test device 100 and apply the aforementioned pealing motion.

Referring still to FIG. 9, the surgical test device may also include positioning tabs 113 extending from the side walls and configured to slidably engage the anvil 24 when the anvil is opened and closed, see FIGS. 7-8. Positioning tabs 113 may help align the distal portion of the test device when opening and closing the anvil 24 with respect to the staple cartridge channel 22.

Referring to FIGS. 9 and 10, when firing the surgical stapler 10, the side walls 102, 103 may tend to flex near the release member 107 as the cutting member 26 is advanced over the release member 107, jeopardizing clearance of the lockout trough 23 by pins 27. Accordingly, the surgical test device may further comprise at least one reinforcing rib 114 connected to and/or formed in the side walls 102, 103. To overcome the aforementioned flexing, the reinforcing ribs 114 may also be located at the same longitudinal position along the body 101 as where the release member is located, see FIG. 10.

Further, referring again to FIG. 9, to better maintain position and alignment at the distal portion of the test device 100 when the release member 107 is engaged by cutting member 26, a raised surface 115 including a boss 116 extending from the bottom wall 105 may be incorporated and/or attached to the body 101. Referring to FIGS. 9 and 10, when the end effector 12 is received in cavity 106, the outer surface of staple cartridge channel 22 may nest on raised surface 115 (see FIG. 9) and the boss 116 may engage a bottom groove of the channel 22 (see FIG. 10). Also, as the cutting member 26 engages the release member 107, the distal portion of the test device 100 may be urged upwards; the boss 116 and/or raised surface 115 accordingly may help prevent the test device 100 from moving undesirably during actuation of the cutting member over the lockout trough 23 (see FIGS. 13B-13C) by stabilizing the distal portion of the test device 100 against the end effector 12.

Additionally, the surgical test device 100, in at least one embodiment may also include one or more of the following. The surgical test device 100 may be attached to a surgical tool, such as stapler 10 (see FIG. 5), before shipping the stapler 10 to a user. Thus, the test device 100 may also help protect the end effector 12 during storage and/or shipment. Also, the surgical test device may be clearly marked for use in test firing only and/or for disposal prior to surgical use.

In various embodiments, a surgical test device may include features to benefit a surgical tool with an articulating end effector. For example, referring now to FIGS. 14-16, various views of a surgical test device 200 are provided. FIG. 14 is a perspective view the test device 200, FIG. 15 is a side cross-sectional view of the test device 200, and FIG. 16 is a bottom view of the surgical test device 200. The test device 200 may be similar to that described above and may include release member 207 extending from body 201, a finger grip (with a visual instruction, “PULL”) also extending from the body 201, and slots 211 defined in the body 211 (see FIG. 16). However, the surgical test device may further comprise a panel 218 hingedly mounted to a proximal portion 217 of the body 201. The panel 218 may be hingedly mounted to the proximal body portion 217 by a living hinge 219 or other known hinges, for example. While the panel 218 is shown in an open position in FIGS. 14-16, the panel 218 may be configured to cover an articulation pivot, such as articulation pivot 14 adjacent to end effector 12 of surgical stapler 10 (see FIGS. 1-2), for example, when in a closed position and when the surgical test device 200 is releasably engaged to the end effector, as described above. The panel 218 may also include a lip 220 extending therefrom that is configured to engage the proximal body portion 217 when the panel 218 is closed, to create a releasable snap fit.

Referring to FIGS. 1-2 and 14, the panel 218 may serve at least two functions. First, the panel 218, when closed and in conjunction with proximal body portion 218, may assist in protecting the articulation pivot 14 during transportation and/or storage of the surgical stapler 10, for example. Second, the panel 218, again when closed and in conjunction with proximal body portion 218, may also help contain or hold lubricant against the articulation pivot 14, until the stapler 10 is ready for use in a patient, at which point, the panel 218 may be opened as seen in FIG. 14, for example, and the test device 200 removed from the stapler 10 by pulling the finger grip 212 away from the stapler 10.

In various embodiments, a surgical test device may engage the lockout mechanism of a surgical tool differently than that described above. For example, while the above-described release members engaged the lockout mechanism of stapler 10 by protruding from outside the end effector 12 and through the staple cartridge channel 22 (see, e.g., FIG. 10), a surgical test device may include a release member that is configured to engage the lockout mechanism without passing through the staple cartridge channel 22, in a manner that may be at least partially similar to the way that a regular, unspent staple cartridge prevents the lockout from functioning.

In at least one embodiment and referring to FIGS. 17-18, a surgical test device 300 may include a body 301 that is sized and configured to fit within a staple cartridge channel 22 (see FIG. 10) in place of a staple cartridge 37 (see FIG. 4). FIG. 17 is a top perspective view of the surgical test device 300 and FIG. 18 is a bottom perspective view of a proximal portion of the test device 300. The surgical test device 300 may further comprise a release member 307 that includes a projection 322 extending from a cantilevered arm 321 formed in body 301. Further, the projection 322, cantilevered arm 321, and/or body 301 may define a slot that is sized and configured to receive cutting member 26 therethrough (see, again, FIG. 4).

The release member 307 may engage the lockout mechanism of a surgical tool, such as stapler 10, as follows. Referring to FIG. 17 for test device 300 and FIG. 11 for the stapler's components, when test device 300 is inserted in staple cartridge channel 22, the notch 32 at the distal portion of cutting member 26 may engage release member 307 at projection 22 and thereby prevent the pins 27 from moving into lockout trough 23. As the cutting member 26 is advanced in a distal direction DD, the cantilevered arm 321 may flex away from the cutting member 26, thereby allowing the cutting member 26 to pass. After the cutting member 26 passes the projection 22, the cantilevered arm 26 may resiliently bend back into the initial position seen in FIG. 18, for example. Accordingly, as with test devices 100 and 200, discussed above, the test device 300 may be used multiple times within the same surgical stapler 10. Notably, the projection 322 may be positioned with respect to body 301 such that the projection 322 may engage the cutting member notch 32 before the cutting member pins 27 move into or otherwise engage the lockout trough 23. Also, as can be seen in FIG. 17, the body 301 does not include any staple cavities or openings therein.

Further, referring to FIG. 17, the surgical test device 300 may further include walls 302, 303, and 304 formed at the distal portion of the body 301. As can be seen, the side walls 302 and 303 may only extend partially along the length of an end effector 12 (see FIG. 1). Accordingly, owing to the lack of a wall along the length of an end effector, a user may not only observe a cutting member moving through an end effector from the bottom of the end effector, but he or she may also directly observe a cutting member moving from the side of the end effector.

In at least one embodiment, referring to FIGS. 19-20, a surgical test device, such as surgical test device 400, may be similar to a staple cartridge 37 (see FIGS. 3-4), except at least that the test device 400 does not include staple cavities, staple openings, or staples or any other form of a sealing member cavity, sealing member opening, or sealing member(s). Additional details regarding a staple cartridge may be found in the aforementioned U.S. patent application Ser. No. 10/687,503, entitled “SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING,” to Doll et al. (issued as U.S. Pat. No. 7,380,695). In more detail, referring back to FIGS. 19-20, the surgical test device 400 may include a body 401 that is sized and configured to engage a staple cartridge channel 22. In particular, the body 401 is designed to fit at least partially within the staple cartridge channel 22 and may comprise a lower portion 401 a and an upper portion 401 b. Further, the body 401 lacks staple or sealing member openings defined in upper surface 423. Referring to FIG. 19, the test device 400 may further include a release member 407 coupled to the body that is configured to engage a lockout on a surgical severing and/or sealing device, such as stapler 10 (see FIG. 20). As can be seen in FIG. 19, the release member 407 may comprise a movable member, such as sled 425, held between lower and upper body portions, 401 a and 401 b, respectively. The movable sled 425 may be similar to sled 38 discussed above with respect to staple cartridge 37 (see FIG. 3). In any event, referring to FIGS. 11 and 19, the sled may include a release surface 424 that is configured to engage the notch 32 at the distal portion of cutting member 26 as the cutting member 26 is advanced in a distal direction DD and thereby prevent the pins 27 from moving into lockout trough 23. As the cutting member 26 is driven distally, the sled 425 may be unable to return to the initial position shown in FIG. 19, and thus the surgical test device 400 may be a single use device. Limiting the test device 400 to a single use may be beneficial to help protect the battery life of an electrically powered surgical stapler, such as stapler 10, as the lockout mechanism may then re-engage the cutting member once the cutting member is returned to it its starting position, as described above.

While surgical test device 400 may include at least three parts (i.e., lower body portion 401 a, upper body portion 401 b, and sled 425), a surgical test device including a movable sled may only have two parts: a body and a movable sled. For example, in at least one embodiment and referring to FIG. 21, a side perspective view of a surgical test device 500 is shown. Similar to surgical test devices 300 and 400, described above, the surgical test device 500 may include a body 501 sized and configured to at least partially fit inside and engage a cartridge channel of a surgical severing and/or sealing device, such as stapler 10 (see FIG. 1). Further, the body 501 does not have staple cavities, staple openings, or staples or any other form of a sealing member cavity, sealing member opening, or sealing member(s). The surgical test device 500 may further include a release member 507 coupled to the body that is configured to engage a lockout on the surgical stapler 10. Similar to that described above, the release member 507 may be a movable member, such as sled 525. However, body 501 may be a single piece and movable sled 525 may be slidably engaged in a slot 511 defined by body 501. For example, the sled 525 may include snap-fit features to allow the sled 525 to be snapped into slot 511. In any event, sled 525 may at least slide in a distal direction DD along slot 511. In use, the sled 525 may function similar to sled 425, described above, at least in that the sled 525 may include a surface (not shown) that is configured to engage the notch 32 on cutting member 26 such that the pins 27 do not engage the lockout trough 23 (see FIG. 11) as the cutting member is advanced in the distal direction DD. Again, as the cutting member is driven distally, the sled 525 may be unable to return to the initial position shown in FIG. 21, and thus the surgical test device 500 may be a single use device and provide various related advantages.

The surgical test device 500 may include walls 502, 503, and 504, similar to that discussed above. At least one wall, such as wall 502 may include a symbol 526 formed, printed, and/or attached thereon that indicates to a user that the test device 500 is disposable.

While the embodiments have been described, it should be apparent, however, that various modifications, alterations and adaptations to the embodiments may occur to persons skilled in the art with the attainment of some or all of the advantages of the various embodiments. For example, according to various embodiments, a single component or step may be replaced by multiple components or steps, and multiple components or steps may be replaced by a single component or step, to perform a given function or functions or accomplish a given objective. Further, the various components described above may be made from a variety of materials. For example, the components may be made from any combination of metal, plastic, and/or a biocompatible material. Additionally, while in at least one embodiment, an electrically powered surgical stapler 10 is described for use with a surgical test device, a surgical test device, according to one or more of the various embodiments described herein, may be used with a manually powered surgical severing and/or sealing instrument, such as the surgical stapler described in U.S. patent application Ser. No. 10/687,503, entitled “SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING,” to Doll et al. (issued as U.S. Pat. No. 7,380,695), mentioned above. This application is therefore intended to cover all such modifications, alterations and adaptations without departing from the scope and spirit of the appended claims.

The devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. In either case, however, the devices can be reconditioned for reuse after at least one use. Reconditioning can include a combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, the devices can be disassembled, and any number of particular pieces or parts of the device can be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, the devices can be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those of ordinary skill in the art will appreciate that the reconditioning of a device can utilize a variety of different techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

The devices described herein may be processed before surgery. First a new or used instrument is obtained and, if necessary, cleaned. The instrument can then be sterilized. In one sterilization technique, the instrument is placed in a closed and sealed container, such as a plastic or TYVEK® bag. The container and instrument are then placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or higher energy electrons. The radiation kills bacteria on the instrument and in the container. The sterilized instrument can then be stored in the sterile container. The sealed container keeps the instrument sterile until it is opened in the medical facility.

Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material. 

What is claimed is:
 1. A surgical instrument, comprising: a surgical tool configured to supply at least one actuation motion to an end effector, wherein the surgical tool is configured to perform an intended surgical function, and wherein the end effector is configured to retain a staple cartridge, the end effector comprising: a firing element configured to translate in response to the at least one actuation motion; and a lockout mechanism configured to prevent translation of the firing element; and a surgical test device releasably engaged to at least a portion of the surgical tool to prevent the end effector from retaining the staple cartridge, wherein the surgical test device comprises a static element configured to permanently overcome the lockout mechanism and permit the surgical tool to supply the at least one actuation motion to the firing element while permanently preventing the surgical tool from performing the intended surgical function when the surgical test device is engaged with the surgical instrument, wherein the static element remains configured to overcome the lockout mechanism without being reset, wherein the surgical test device does not comprise deployable fasteners, and wherein the surgical test device comprises: a body comprising at least two side walls and a bottom wall, wherein the side walls extend from the bottom wall, wherein the side walls and the bottom wall define a cavity, and wherein the cavity is releasably engaged to the end effector; wherein the surgical instrument further comprises an articulation pivot adjacent to the end effector, wherein the surgical test device further comprises a panel hingedly mounted to the body and configured to cover the articulation pivot when in a closed position.
 2. The surgical instrument of claim 1, wherein the intended surgical function comprises ejecting at least one sealing member from the end effector.
 3. The surgical instrument of claim 1, wherein the intended surgical function comprises inserting at least a portion of the surgical tool through a trocar.
 4. The surgical instrument of claim 1, wherein the intended surgical function comprises inserting tissue into the end effector.
 5. The surgical instrument of claim 1, wherein the end effector comprises a movable jaw member, and wherein the movable jaw member is configured to move between the side walls.
 6. A kit, comprising: an end effector, comprising: a cartridge channel configured to receive a staple cartridge; a translating element configured to translate at least partially through the staple cartridge; and a lockout mechanism configured to prevent translation of the translating element; the staple cartridge positionable in the cartridge channel and comprising deployable staples, wherein the staple cartridge is configured to overcome the lockout mechanism when positioned in the cartridge channel; and a surgical test device, comprising: a body comprising at least two side walls and a bottom wall, wherein the side walls extend from the bottom wall, wherein the side walls and the bottom wall define a cavity, and wherein the cavity is sized and configured to receive at least a portion of the end effector, the body configured to prevent the end effector from retaining the staple cartridge; and a static release member coupled to the body, wherein the static release member is configured to permanently disengage the lockout mechanism to permit the translating element to move distally beyond the lockout mechanism while the surgical test device permanently prevents the end effector from performing an intended surgical function when the at least a portion of the end effector is received in the cavity, and wherein the static release member remains configured to overcome the lockout mechanism without being reset; wherein the surgical test device does not comprise deployable staples; and wherein the end effector further comprises a first jaw member and a second jaw member, wherein the second jaw member is movable between an open position and a closed position with respect to the first jaw member, wherein the bottom wall is adjacent to the first jaw member, and wherein each sidewall extends away from the bottom wall, past the first jaw member, and past the open position of the second jaw member.
 7. The surgical test device of claim 6, wherein the static release member comprises a protrusion extending from the body.
 8. The surgical test device of claim 6, further comprising at least one rib connected to at least one of the side walls and located at a longitudinal position along the body, wherein the static release member is located at the longitudinal position. 